Electric heater.



H. B. GALE. .ELBGTRIG BEATER APPLICATXON FILE) D Patented Apr. 18, Ql.

5 .01, z JJ. 56

l amm- -lumm PAM@ HORACE B. GALE, OF NTCK, MASSAHUSETTS, ASSIGNOE IDO SEMPLEK ELECTRIC HEATING COM'PNY, 0F CAMBRDGE, MASSACHUSETTS, A GOREOBAATION 0F MASS- CEUSETTS.

nnnofeno HEATER.

SD.. @riginal application lez September Specification of Letters Patent.

Pzitenteilpr. 1S, 1h11.

19, 1916, Serial No. 5593)?53. Divided and this applcatonled lecembei 29, 1916. Serial No. 599,981.

To all whom it may concern: y i

Be it known that l, Hennen Bf. Glenn, e citizen of the United States, residing at 'Natiek, in the county of Middlesex ond State of ll/iiesnchuleetts, linveinvented an Improve ment in Electric Heaters, of which the following deocriptioinin connection with the accompanying (iran-'ingo7 is n Specification,

, `likeletteie on the drawings representing,n like parte. t

This invention relates `to en eleetiio heat ing device adapted io collect nn'l conserve the heat generated in resistance elenientsby f the message oi current therethroughn While the device lhas other sind more general fields of usefulness,'one particular op plication is in connection with a method and apparatus` for equelining temperature described and claiincilin my copenling appli# cation Ser. No. 582,753 iiled Sept. 19, 1910, of which this ense is o; division.

The Objects of the invention iiey to provide a construction in simple, comp-iet ifoixn,linving `relatively large lient-generating and f storing capacity, sind other matters of detail ne will hereinafter zuipen?. l kThe invention will he clearly understood from. the following description in connection with the accompanying drawings, wherein Figure lis o centsfel vertical section through the improved heater on line 1-1 Fig. f1; Fig. 2 iS :i sectional detail of e le sistencia element: on line 2-2 of Fig. 3; Fig. 3 is e plan View of n resistance element; end Fig. l1 is n transverse seotion through the heater on line 1r-1 of Fig. 1.`

The heater easing 1, usually inode of iron or other metel, is, shown es oi cylindrical is obviously not metei'ial. The cover 2 oi this casing has depentling therefrom a 'series'l oi rods l iextenlingr downwoicl tofnem' the piece strip or loirwith a series of radial arms, shown es Six, extending in e common plone so to hinge a general. fiat form.

The hob of .thesesections has an enlarged central opening 10 with Slits 11 extending therefromcentrally of each arm and' termi-A noting' in eiilorged openiifigs v 12 leicljaeent, the

enel ol each erm. A. central guide shown as e tuloe 13 is fixed in depending relation to the eove 2, and :in

insulating; sleeve 14 slipped thereover isi-hel@ in position by n cap 15 fixed to the end o seid tube. The resistance elements aref slipped over the several rods Sand tube 13,` the openings 12 being shaped ,to klit around the insulating' Sleeves 6, and the huh openH ing 10 being shown as somewhat larger than the insnlatingeleeve 111. Insulating washers 16 are interposed between the'several icesistance elements and between the lowenresistance elementl and the cap 15,k and like insulating washers are interposed between the extremities of theeevei'el arms of Successive resistance elements fitted over the vi'ocls 3 except two opposite arms 17, 18 oi' erich resistance element, through which ihe eleotrienl connection between successive elemente and tothe terminals is Inode. :Urin 1S. oi the uppei'iresistnnee element eontecte with u block 19 connected with one teiqq ininzil E3() oi the henter1 this liloclheingim snleteol from the cover oy en insulating block 21. This erm insulated ii'oxn the :uljaeentnrni of the next. resistance element by :in iiiqnileting washer' 22., like resistance The imsheiheing interposed to leave the Socie!) ces, ive` :irme 1S electrically oonneetec'l in when there heine: en insulntino washer loetween 'eheh pair, `The opposite zinns 1'? :ire likewise 'electrically connected in paire9 like insulating washers 23 heing'- interposed lietwe'en paire, and the wnehei'e 22, 23 at op posit/e sides being interposed between, alten nnte' resistance elemente, so that. current eny tering ihe erm 18015 the top reeisstnnoe ele- -ment will `page,through looth sides' of eneh inteiinediete'zu'in Q4, Q5, 26,27 at either side to the opposite fu-ni 17, thence in likeinennel.' through the next resistance element 1n opposite direction haelt to the next nini 18, and so on through the series otelements enti iinally ont, from the` lower iightheml arm 17 of the hist resistance element through y the metnllic washer 7 :intl right-heini i'ocl 3 to the other terminal 28, this terminal being insulated from the cover by suitable insulating Washers AA portion of a circuit controller' is shown, consistin,r of a metallic rod 30 adapted to he expanded by heat, which is disposed within the tube 18, rests on the bottom of the casing, and at its top is arranged to press against a spring contact bar 3l, and thns close a contact through terminals 32, 33 of a secondary circuit which, when closed, is arranged to open the main circuit, as more full3Y explained in my co-pending application to which reference is above made.

The heater casing is preferably made of massive construction so as to Ilford alarge heat-storing capacity, and the internal surface 1hereotl is desirably made in a scalloped section, as shown at 34 in Fig. Il, in order to bring all parts of the heating resistance into Vas close proximity as possible to the heatahsorbing surface thereof, and to facilitate heat transmission between the resistance element and the casing by providing the largest practicable extent of transmitting surface within a given space. The resistance elcrnent in the forni of a scalloped and slit ring with radiating arms, presents a form which has a considerable length of conductor .in a compact space, every portion of the conductor moreover being exposed on the outside to free radiation of heat to the opposite surihglce of the casing l and also free lo expand toward the center when heated. "lhis torni is also adapted to be easily cast and economically insulated and supported by suspension rods in the case, as' shown. .lf desired, the entire resistance element may be lifted out ol the case by raising the cover plate, and inspected without loosening screws or other parte. On account of the substantial mass of heat yoring metal thus provided, it obvious that; the heat deliverable h); the heater will he to a large extent inde- Lufndcnt of temporary fluctuations in the .:urront supply, the heater thus having an exccptionally high capacitv for uniform heat deliver): in very compact forni.

llaving de 1cribcd my invention, what. l claim as new and desire lo secure by Letters Patent is,

l. .ln electric heater, comprising :y resistance conductor formed as a series of conduc4 tive sections with radiating arms,insulation separating the sections except at alternate opposite points, and 'a casing conforming in interior shape to the external forni of said sections.

2. Au electric healer, comprising a resistance conductor composed of a' series of flat conduct-ivo sections, insulation separating the sections except at alternate opposite points, and a casing having parts in inlinediate heat-receptive relation to .all parts of said conductor.

3. ln an electric heater, a resistance elcment compos d of flat conductive plates having a hab with an enlztrged central opening and a series of arms radiating therefrom, each of said arms having an ci'llargged opening atits extremity to receive o snm and. a slit extending from said opening tt said hub opening.

-l. ln an electric heater, a resistance conductor composed ot e series of conduct.' 'e plates, each having a central huh and 'radial arms, said plates having insulation disposed therebetween and being divided so that current introduced at an extremity of one anni will pass through all the arms of the successive plates.

5. In an electric heater, a resistance con-v dactor'comprising a series of conductive clef ments, each with a hollow centfal hul and radial arms, each of said arms being slitlied from the hollow of the hub to near its extremity, and electric conn yction to non-adj cent arms of each element, whereby current will pass through each element partly in multiple and partly in series tl. An electric heater, comprising n, resistance conductor composed ol' a scricf-L o' flot condnclhf'e elements. each having a hollow huh and slitted radial arms, insulation arranged so as to leave non-adjacent crine et Ysuccessive elements electrically connected, a

casing, a cover therefor, and ineens #for clamping said conductive elements and insulation in assembled relation to said cover.

7. ,in electric heater, comprising a resistance cornluctor compo fd olf a series of l conductive elements, cach having a hollenA huh and slitted radial arms, insuletion arranged so as to leave non-adjacent lirios of' successive elements electrically connected, and a. casing, having its inner walls lying adjacent and conforming in share to the external liorln or' said. resistance conductor.

S. An electric heater, comprising a. resistance conductor composed ot a set of flat "onductivc sections electrically connected pairs at opposite pointe, insulation ing the scclions' alternately hctwccn pairs, and a casing; having a parlv on which said sections are adapted to he sliilably assembled.

ln testimony whereof. l have signed my naine to thi." spcciflcalimi, in the presence ol two subscribing witnesv HORA. CE B. 

